Switch lock construction



May 28,? 1940. R. L. sMYTHE SWITCH LOCKv CONSTRUCTION 2 Sheets-Sheet 1 INVENTOR.

ATTORNEY.

May 28,y 1940, R. l.. sMYTHE SWITCH LOCK CONSTRUCTION 2 Sheets-Sheet 2 Filed oct. 5o, 19:57

@www INVENTOR.

ATTORNEY,

Patented May 28, 1940 i UNITED STATES PATENT OFFICE SWITCH LOCK CONSTRUCTION Application October 30, 1937, Serial No. 171,902

1 Claim.

This invention relates to improvements in electric switch latch means.

The principal object of this invention is to provide for blade type switches, latching mechanism which is automatically operated to release the switch blade for manual movement to opencircuit position.

Another object is to provide latching mechanism which is automatically withdrawn from latching position relative to the switch blade While the blade is being manually moved to circuit-closing position and which will immediately latch the blade in circuit-closing position when the circuit-closing movement has been completed and the moving force has been withdrawn.

More specifically, it is an object to provide manually operable means for rendering the latch inoperative and concomitantly operating the switch blade and means for rendering the latch operative when the manually operable means is released.

A further object is to provide a durable, sirnple and eilcient switch and latch-operating mechanism which is positive in action and protected against damage.

In the drawings:

Fig. 1 is a view in side elevation showing a switch embodying this invention.

Fig. 2 is a fragmentary top plan View of the device shown in Fig. 1.

Fig. 3 is a sectional View taken on the line 3--3 of Fig. 1.

Fig. 4 is an enlarged fragmentary View in side elevation showing the latch-operating mechanism.

Fig. 5 is an enlarged sectional View takenon the line 5-5 of Fig. 4.

Fig. 6 is an enlarged sectional view taken on the line 6 6 of Fig. 4.

Like parts are identied by the same reference characters throughout the several views.

The switch structure disclosed in the drawings comprises a base plate I adapted for attachment to a support, not shown, a pair of relatively spaced insulator blocks 2 and 3 secured to the base plate I by means of bolts 4, a pivot standard 5 secured to the block 2 by means of stud bolts 6 and having a terminal strip l, a contact member 8 secured to the block 3 -by means of stud bolts 9 and having a terminal strip I0, a pair of relatively spaced guiding horns II and IIB secured to the member 8 by means of the bolts S, a pair of relatively spaced resilient contact brushes I2 positioned between the horns II and IIB and secured to the upright portion I3 on the contact member 8 as indicated in Fig. 3, and a switch member A pivotally mounted at one end on the pivot standard 5 and electrically engaged adjacent its other end by the brushes The switch member A comprises a pair of relatively spaced parallel switch blades I4 and I5 which are mutually pivoted on the standard 5 by means of the pivot rod I6 and connected at their free ends by means of the pivot pin II upon which the switch-operating pull ring I84 is pivotally mounted. In order to hold the free ends of the blades I4 and I5 in predetermined spaced. relation, the pin I'I is enlarged at I9 between the blades and provided with nuts 20 securing the blades upon the pin.

As indicated in the drawings, the pull ring I8 is reduced in width at its pivoted end to` provide a flat pivot arm 2I and space 22 between the arm 2l and blade I4 for reasons which will hereafter appear. Remote from the pull ring, a pivot block 23 is mounted between the blades I4 and I5 in any suitable manner, as by pins 24 extending into adjacent blades, and is positioned above the elongated aperture 25 in the blade I5.

A latching lever 26 is pivotally connected intermediate its ends with the lower face of the pivot block 23 at 21 and extends through the aperture 25 in the blade I5. Positioned between the blades I4 and' I5 is a freely movable link member 28 which is pivotally connected at 29 with the latch lever 26 and which is apertured at 3U for sliding movement upon the pin Il. The link 28 is provided with an elongated recess 3| within which a coil spring 32 is mounted and is held under compression by means of the stud 33 in the blade I5. The slidable end of the link 28 is provided with laterally extending ears 34, each of which engages an adjacent roller 35 supported by a pin 36 on the pull ring pivot arm 2|.

Normally the spring 32, by reason of its strained condition between the link 28 and the stud 33, urges the link toward the pivot end of the switch and thereby maintains the latching lever 26 in its latching position as shown. Inthis position, the lever 26 extends beneath the catch 3'! which extends from and is an integral portion of the horn IIB.

When it is desired to open the switch, a hookoperating stick, not shown, is engaged with the pull ring I8 and pushed upwardly in the direction of the arrow 38 in Fig. 4. As a consequence of this, the pull ring I8 will rotate in the same direction about its pivot pin Il and through the lower pin 3B and roller 35, and the lower ear 34 will move the link 28 toward the pull ring and cause the latching lever 26 to be withdrawn, about its pivot, from beneath the catch 31 and to a position between'the blades |14 and l5.

After the lever 26 has been thus withdrawn, one end of the aperture 30 in the link 28 will contact the pin il and prevent further pivotal movement of the pull ring I8. The pull ring will then serve as a means for moving the switch about its pivot I6 to open-circuit position.

Upon removal of the operating stick, not shown, from the pull ring I8, the spring 32 Will automatically move the latching lever to its latching position relative to the switch blade.

A similar result is obtained when'x the switch is being moved to circuit-closing position. The pull ring i8 will be rotated in the direction indicated by the arrow 39 and through the upper pin 36, roller 35 and ear 36, and the link 2B will Withdraw the latching lever 215 from its latching position. The end of the slot 30 previously noted will then engage the pin H and render the pull ring I3 operative for closing the switch. When the switch has been moved to its circuit-closing position and the pull ring released, the spring 32 will position the latching lever beneath the catch 31.

From the foregoing, it will be observed that a switch has been provided in which the force exerted to move the switch to or from its circuit-closing position is utilized to Withdraw the switch-latching mechanism from its latching position before the switch is moved and that the mechanism for accomplishing these results is easily manufactured, assembled and operated.

I claim:

In an electric switch structure comprising a switch including a pair of substantially parallel switch plates having a common pivot at one end, and a pair of resilient contacts receiving said plates between them at the other end, one of said plates having a latch-receiving aperture, the combination with a switch-operating memu ber pivotally mounted between said plates at said other end, of a latch pivotally mounted between said plates for movement through said aperture, said latch normally extending laterally of said apertured plate to the exterior of the space between said plates, a link pivotally connected with said latch and interengageable with said member for moving said latch through said aperture in either direction of movement of said switch, the connection of said link and member permitting movement of said link independently of movement of said member, a spring biasing said link against independent movement, and a catch distinct from said contacts and disposed laterally to one side of the direction of movement of said switch for engagement by said latch, whereby direct contact between said latch and resilient contacts is avoided.

ROBERT L. SMYTHE. 

